The application envisioned for the disclosed device is mainly for manually performed procedures in which an operator takes each individual dosage unit out of a holding rack and places it into a dispensing setup, typically a dosage-dispensing setup that couples to a shutter- and/or feeder element in the dispensing head of the dosage unit to deliver a measured quantity of powder from the dosage unit into a receiving container. The manual process of taking dosage units from the rack and placing them in the dispensing setup involves the risk of operator errors for example if a plurality of different powders are to be dispensed sequentially into the same receiving container. If, for example, the user accidentally dispenses a dose of powder twice from the same container, the resulting mixture in the receiving container will have the wrong mix ratio.
The process of mixing substances in this manner is used for example for standards for the calibration of HPLC (High Performance Liquid Chromatography) instruments which has to be performed in accordance with regulatory requirements. Such standards are mixtures of different pulverous substances which, as a rule, are mixed together and dissolved in an appropriate solvent right before they are used, because if the individual components were kept in a mixed state and/or solved over a longer storage time period a destruction reaction could take place.
Therefore, in view of the need to prepare mixtures of different powders in a laboratory and to avoid the risk of operator errors of accidentally dispensing the same powder dosage component into the batch twice or forgetting a component, the object is to provide a laboratory setup with a holding rack for dosage units which has a degree of intelligence which ensures that each dosage component is dispensed into the target batch only once and no dosage component is accidentally omitted from the target batch.